Cognomen Namsaeng (Namsaeng 
) , globally, is a rare surname. The cognomen Namsaeng is habitual in Thailand, where it is quite a rare surname, and Canada, where it is an extremely rare surname.
Sam, Chanon, Namfon, Nobporn, Nutawut, Ngamta, Maliwan, Siwarut, Sompong, Somchat, Adundet, Aumphai, Chamhom, Caonlada, Bualiam, Kunanek, Kraiwit, Patsaya, Paitoon, Ponnapha, Phattra, Pharada, Aoeitan, Apinya, Amphon, Somyot, Suk, Dee, Noi, Num, Mhai, Auey, Kaew, Kham, Paer, Yeam, Rattana, Ying, Saran, Saita, Saeng, Sawat, Sumet, Kamon, Thewa, Wanna, Sawart, Sunisa, Manop, and Ladawan